James Roy Horner (born August 14, 1953) is an award winning American composer, orchestrator and conductor of orchestral and film music. He is noted for the integration of choral and electronic elements in many of his film scores, and for frequent use of Celtic musical elements.

In a career that spans over three decades, Horner has composed several of Hollywood's most famous film scores. He is probably best known for his critically acclaimed works on the 1997 film Titanic, which remains today the best selling film soundtrack of all time. Other popular works include Braveheart, Apollo 13, The Mask of Zorro, and The Legend of Zorro.

Horner is a two time Academy Award winner, and has received a total of 11 nominations. He has won numerous other awards, including the Golden Globe Award and the Grammy Award.